St. Augustine: “I intend to remind myself of my past foulness
and carnal corruptions, not because I love them but so that I may love
you, my God. It is from love of your love that I make the act of recollection.
The recalling of my wicked ways is bitter in my memory, but I do it so
that you may be sweet to me, a sweetness touched by no deception, a sweetness
serene and content…To whom do I tell these things? Not to you, my
God. But before you I declare this to my race, to the human race, though
only a tiny part can light on this composition of mine.”

St Augustine wrote page after wordy page about his sin and his grief.
He did it to give hope to other sinners. His main focus was his childhood
and the fact that confession should be public.

Jean-Jacques Rousseau “I wish to show my fellows a man in all
the truth of nature; and this man will be myself…I have shown myself
as I was, contemptible and low when I was so, good, generous, sublime
when I was so; I have unveiled my interior as Thou hast seen it Thyself.”

Rousseau wrote Confessions of Jean-Jacques Rousseau mainly
to tell the world that he thought he was better than them. He spent a
lot of time confessing his first adolescent stirrings of sexual feeling.

Thomas DeQuincey “This is the doctrine of the true church on the
subject of opium: of which church I acknowledge myself to be the only
member—the alpha and the omega: but then it is to be recollected,
that I speak from the ground of a large and profound personal experience.”

DeQuincey wrote Confessions of an English Opium-Eater, which
told how he did more opium than any other man alive, and lived to tell
the tale. His confession confirmed that he was a gentleman--he never became
a beast in the throes of addiction.